CN116620791A - Chain jump protection system and protection method for scraper conveyor - Google Patents
Chain jump protection system and protection method for scraper conveyor Download PDFInfo
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- CN116620791A CN116620791A CN202310381425.0A CN202310381425A CN116620791A CN 116620791 A CN116620791 A CN 116620791A CN 202310381425 A CN202310381425 A CN 202310381425A CN 116620791 A CN116620791 A CN 116620791A
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- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000005303 weighing Methods 0.000 claims abstract description 32
- 230000003750 conditioning effect Effects 0.000 claims abstract description 31
- 230000005540 biological transmission Effects 0.000 claims abstract description 18
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 238000006073 displacement reaction Methods 0.000 claims abstract description 4
- 239000003245 coal Substances 0.000 claims description 15
- 238000006243 chemical reaction Methods 0.000 claims description 12
- 238000001514 detection method Methods 0.000 claims description 5
- 238000009434 installation Methods 0.000 claims description 4
- 238000005259 measurement Methods 0.000 claims description 4
- 239000000725 suspension Substances 0.000 claims description 4
- 238000004458 analytical method Methods 0.000 claims description 3
- 239000003638 chemical reducing agent Substances 0.000 claims description 3
- 238000013016 damping Methods 0.000 claims description 3
- 238000007665 sagging Methods 0.000 claims description 2
- 238000009795 derivation Methods 0.000 claims 1
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- 238000012544 monitoring process Methods 0.000 abstract description 10
- 238000013461 design Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000033001 locomotion Effects 0.000 description 4
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- 238000005065 mining Methods 0.000 description 2
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- 230000007547 defect Effects 0.000 description 1
- 230000010006 flight Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
- B65G23/00—Driving gear for endless conveyors; Belt- or chain-tensioning arrangements
- B65G23/44—Belt or chain tensioning arrangements
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
- B65G19/00—Conveyors comprising an impeller or a series of impellers carried by an endless traction element and arranged to move articles or materials over a supporting surface or underlying material, e.g. endless scraper conveyors
- B65G19/18—Details
- B65G19/20—Traction chains, ropes, or cables
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
- B65G43/00—Control devices, e.g. for safety, warning or fault-correcting
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Abstract
The application discloses a chain jump protection system and a protection method of a scraper conveyor, wherein the system comprises a chain wheel vertical fine adjustment mechanism, a stress sensor, a weighing sensor and a laser ranging sensor, wherein the sensor is also connected with a signal conditioning box, so that various sensor signals are converted into signals which can be identified by an industrial personal computer, then an upper computer identifies the meshing state of a scraper chain and the chain wheel based on data signals input by the industrial personal computer, the chain tension of the scraper conveyor and a threshold value of the overhang quantity, and realizes chain jump monitoring, and the chain jump protection system further comprises a vertical tensioning hydraulic cylinder and a constant-speed universal transmission shaft structure, so that the oil liquid quantity entering the hydraulic cylinder can be changed in real time to control the vertical displacement of the chain wheel. According to the method, the digital signal is converted into the current signal which can be identified by the servo valve through the signal conditioning system, so that the cooperative control of the horizontal tensioning hydraulic cylinder and the vertical tensioning hydraulic cylinder is realized, the real-time control of the tensioning force of the scraper chain and the protection of the chain jump of the scraper conveyor are ensured, and the reliable and stable operation of the scraper conveyor is better ensured.
Description
Technical Field
The application relates to the technical field of monitoring and safety guarantee of scraper conveyors, in particular to a chain jump protection system and a protection method of scraper conveyors.
Background
The scraper conveyor is used as a mining continuous conveying device for conveying coal by means of scraper chains, and plays important roles of conveying the coal, providing a pushing pivot for a hydraulic support and providing a traveling track for a coal mining machine, and the reliability of the scraper conveyor directly affects the safe and efficient production of modern coal mines.
Chains are the most prone mechanism to failure of the scraper conveyor, and the failure (chain breakage, chain jump, chain drop, etc.) accounts for about 21.1% of the total number of failures of the scraper conveyor. Once the chain of the scraper conveyor has faults such as chain jump and the like, the required maintenance time is long, and the production efficiency of large coal mines in China is severely restricted. At present, chain tension and hydraulic cylinder tension of the scraper conveyor are indirectly obtained mainly through oil cylinder pressure, chain suspension amount, load torque and the like at home and abroad. In the operation process of the scraper conveyor, the total tension of all chains of the scraper conveyor can be only obtained through the pressure and the power of the oil cylinder, and the respective tension of the chains is difficult to realize effective monitoring. The scraper conveyor chain realizes the transportation of coal through endless closed loop movement, and the traditional wired measurement mode is difficult to realize the real-time direct monitoring of chain tension. The application discloses a chain tension monitoring device and a method of a scraper conveyor, and the application discloses a chain tension monitoring device and a method of the scraper conveyor, which are used for converting the monitoring of the chain tension of the scraper conveyor into real-time detection of chain wheel stress in a wireless transmission mode and judging whether the chain tension is overrun, whether chain breakage occurs or not and the specific chain in which the chain breakage occurs based on the acquired stress data. The monitoring method is flexible and reliable, has limited application range, can be only used for observing the chain breakage condition of the scraper conveyor, and cannot quickly and accurately identify the chain jump condition and the like.
The above problems need to be solved.
Disclosure of Invention
Aiming at the defects in the prior art, the application aims to provide a chain jump protection system of a scraper conveyor, so as to solve the problems in the prior art.
According to one aspect of the application, the chain jump protection system of the scraper conveyor comprises a chain wheel vertical fine adjustment mechanism, a middle groove of the scraper conveyor, a weighing sensor, a horizontal tensioning hydraulic cylinder, a vertical tensioning hydraulic cylinder, a laser ranging sensor, an external upper computer, an industrial personal computer and a signal adjustment box, wherein the right side of the chain wheel vertical fine adjustment mechanism is fixedly connected with a motor of the scraper conveyor, the motor is fixedly arranged, a chain wheel of the scraper conveyor is rotatably arranged on a chain wheel base through a chain wheel shaft, the chain wheel base is movably arranged, the left side of the chain wheel vertical fine adjustment mechanism is connected with the chain wheel shaft, a stress sensor is arranged on the side surface of the chain wheel teeth, a laser ranging sensor is arranged on one side of the chain wheel vertical fine adjustment mechanism, the weighing sensor is arranged in the middle groove of the scraper conveyor, the vertical fine adjustment mechanism of the chain wheel is fixedly connected with the vertical extension end of the vertical tensioning hydraulic cylinder, the bottom of the vertical tensioning hydraulic cylinder is connected with the ground through a sliding rail, the vertical tensioning hydraulic cylinder can synchronously and transversely move with the chain wheel base, the horizontal tensioning hydraulic cylinder is horizontally arranged on the ground, the extension end of the horizontal tensioning hydraulic cylinder is fixedly connected with the chain wheel base, the stress sensor is used for measuring stress data of chain wheel teeth under different chain tensions in the operation process of the scraper conveyor, the weighing sensor is used for measuring coal dropping weight in each operation period of the scraper conveyor, the laser ranging sensor is used for measuring the vertical distance from a meshing point of the chain wheel and the chain wheel to a middle groove of the scraper conveyor, the stress sensor, the weighing sensor and the laser ranging sensor are electrically connected with the signal conditioning box, the signal conditioning box is electrically connected with an industrial computer, the industrial personal computer is electrically connected with the upper computer, the signal conditioning box can condition output signals of the stress sensor, the weighing sensor and the laser ranging sensor into voltage signals which can be identified by the industrial personal computer, and the industrial personal computer transmits data acquired by the stress sensor, the weighing sensor and the laser ranging sensor to the upper computer through a TCP/IP protocol.
Preferably, the vertical fine adjustment mechanism of sprocket includes connector, stress sensor, sprocket shaft and constant velocity universal drive shaft structure, the end that stretches out of vertical tensioning pneumatic cylinder passes through connector and constant velocity universal drive shaft structure fixed connection, constant velocity universal drive shaft structure with sprocket shaft fixed connection, constant velocity universal drive shaft structure and the output shaft fixed connection of scraper conveyor's motor.
Preferably, the constant velocity universal transmission shaft structure comprises a middle shaft, a universal adjusting piece, a steering shaft, a connecting disc, a connecting shaft and a gear box, wherein the universal adjusting piece is fixedly connected with the extending end of the vertical tensioning hydraulic cylinder through a connector, the universal adjusting piece is fixedly connected with the sprocket shaft through the middle shaft, the universal adjusting piece is in spherical hinge connection with one end of the steering shaft, the other end of the steering shaft is in meshed transmission connection with the gear box through a gear, the gear box is fixedly connected with the connecting disc through the connecting shaft, and the connecting disc is fixedly connected with the output shaft of the motor.
Preferably, a digital signal conversion module and a control signal conversion module are arranged in the industrial personal computer, an analog quantity input conditioning module and an analog quantity output conditioning module are arranged in the signal conditioning box, the analog quantity input conditioning module transmits output signals of the weighing sensor and the laser ranging sensor to the industrial personal computer through the digital signal conversion module, the industrial personal computer transmits control signals to drive the servo valve through the control signal conversion module and the analog quantity output conditioning module, so that oil liquid output to the vertical tensioning hydraulic cylinder and the horizontal tensioning hydraulic cylinder is controlled to be used for realizing adjustment of chain tensioning force, data acquired by the weighing sensor and the laser ranging sensor can be transmitted to the upper computer through a TCP/IP protocol to be calculated and stored, and data acquired by the stress sensor is transmitted to the upper computer through a DH5960 data acquisition device through a gigabit Ethernet.
Preferably, the laser ranging sensor is a ZYT-405 type regional ranging detection control sensor, and the horizontal tensioning hydraulic cylinder and the vertical tensioning hydraulic cylinder are servo valve control type hydraulic cylinders.
The protection method of the chain jump protection system of the scraper conveyor specifically comprises the following steps:
in one working period of the scraper conveyor, establishing a correlation model of chain tension of the scraper conveyor and stress at the installation position of the stress sensor through a dynamics principle; the installed stress sensor is checked through an external standard tension sensor, and the chain tension of the scraper conveyor is obtained through the output of the stress sensor; the stretching force of the horizontal stretching hydraulic cylinder is obtained according to the obtained chain tension and the data measured by the weighing sensor by utilizing the derived dynamic model, so that the stretching of the horizontal stretching hydraulic cylinder is controlled to control the stretching of the chain of the scraper conveyor to stretch the chain in the horizontal direction;
measuring the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove of the scraper conveyor by using a laser ranging sensor; judging whether the chain has a chain jump fault or not through judging the fault of the scraper conveyor; on the basis of determining the chain jump fault, the tensioning force of the vertical tensioning hydraulic cylinder is obtained by combining data measured by the laser ranging sensor, the stress sensor and the weighing sensor, and the vertical tensioning hydraulic cylinder is controlled to extend so as to control the chain wheel to move upwards to tension the chain, so that the chain jump fault is prevented.
Preferably, the association model of the chain tension and the stress at the installation position of the stress sensor is that the stress change of the corresponding positions of the tension of the chain of the scraper conveyor and the side surface of the sprocket tooth is measured in real time through the stress sensor arranged on the side surface of the sprocket tooth, so that the measurement of the chain tension is realized.
Preferably, the deriving of the kinetic model comprises:
the moment balance equation of the chain wheel is as follows:
in the formula (1), θ m And theta s Angular displacement of the driving device and the sprocket respectively; j (J) m Equivalent moment of inertia for the tail sprocket drive; b (B) m Is a damping coefficient; m is M m And M s The output torque of the motor and the load torque of the chain wheel are respectively; z is Z s Is the transmission ratio of the gear reducer; r is R 0 The pitch circle radius of the chain wheel is mu, the friction coefficient of the surface of the middle groove is mu, G is the weight of randomly falling coal, and L is the center distance of the chain wheels at the tail of the machine head;
combining the linear mass density lambda of the chain and the boundary condition y' (L-a/2) =0, the suspension chain sag equation of the tail-side EF section is established as follows:
wherein a is the length of the catenary in the horizontal direction; t (T) F The chain tension at the point F is measured by the stress sensor (1.2);
the formulas (1) and (2) are combined and decomposed along the horizontal and vertical directions to obtain the horizontal and vertical tensioning hydraulic cylinder tensioning forces which are respectively as follows:
F h (T F ，G，h E ，h B )＝(μGL/R 0 -T F /cosα)/cosβ+T F formula (3)
F v (T F ，G，h E ，h B )＝(μGL/R 0 -T F Formula/sin alpha/sin beta (4)
Wherein the engagement angles alpha and beta can be obtained by chain configuration analysis:
wherein S is 1 And S is 2 The chain lengths of the loaded side and the unloaded side are respectively h B And h E The chain sag is the load and no load side respectively.
Preferably, the coal falling weight G is taken as a constant value and is measured by the load cell, and the chain tension T F The sagging amount h is measured by the stress sensor B And h E Are all measured by the laser ranging sensor.
Preferably, the specific steps of fault discrimination of the scraper conveyor are as follows:
(a) Firstly, setting the vertical distance between the lower meshing point of a chain wheel and a chain and the bottom plate of a middle groove of the scraper conveyor and the safety threshold value of the tension value of the chain as X and Y according to historical data under the normal operation condition of the scraper conveyor;
(b) Then, respectively judging whether the vertical distance from the lower engagement point of the chain wheel and the chain of the scraper conveyor to the bottom plate of the middle groove of the scraper conveyor and the tension value T of the chain are larger than set safety thresholds X and Y, wherein the specific judging method is as follows:
(b1) If not, the industrial personal computer outputs a tension non-overrun signal;
(b2) If the vertical distance from the lower meshing point of the chain wheel and the chain to the middle groove bottom plate of the scraper conveyor is lower than a safety threshold X and the ratio of the tension value T of the chain to the tension threshold Y is suddenly changed, the industrial personal computer outputs a broken chain judging signal of the scraper conveyor;
(b3) If the vertical distance from the lower meshing point of the chain wheel and the chain to the middle groove bottom plate of the scraper conveyor does not exceed the safety threshold X but the chain tension value T exceeds the set safety threshold Y, the industrial personal computer outputs a scraper conveyor chain clamping judging signal;
(b4) If yes, the industrial personal computer outputs a scraper conveyor chain jump judging signal;
(c) And finally, once the upper computer receives a chain jump judging signal of the scraper conveyor, controlling the vertical tensioning hydraulic cylinder to act, so as to drive the chain wheel to move upwards to tension the chain, and preventing the occurrence of chain jump accidents.
Compared with the prior art, the application has the advantages that:
(1) Compared with the traditional single transverse adjustment mode of chain tension of the scraper conveyor, the application designs the vertical fine adjustment mechanism of the chain wheel, realizes the vertical fine adjustment of the chain wheel to tension the chain by utilizing the constant-speed universal transmission shaft structure and the vertical tensioning hydraulic cylinder, and is easy to slightly shift when mechanical parts are matched due to the fact that the universal adjustment device of the constant-speed universal transmission shaft structure is connected with the steering shaft through the precise spherical hinge, and is easier to realize the meshing of the chain wheel and the chain.
(2) The application converts the monitoring of chain tension of the scraper conveyor into the real-time detection of chain wheel stress, judges the fault condition of the chain of the scraper conveyor based on the on-line monitoring of the chain tension and the overhang quantity, and controls the running state of the chain by using the horizontal and vertical tensioning hydraulic cylinders.
(3) The application not only designs a chain jump protection method of the scraper conveyor, but also designs a chain tension adjusting method based on time-varying load during normal operation of the scraper conveyor, which is beneficial to improving the reliability and safety of the operation of the scraper conveyor.
Drawings
Fig. 1 is a schematic structural view of a chain jump protection system for a scraper conveyor according to an embodiment of the application.
Fig. 2 is a schematic diagram of a vertical fine adjustment mechanism for a sprocket of a chain jump protection system for a scraper conveyor according to an embodiment of the present application.
Fig. 3 is a control schematic diagram of a chain jump protection system for a scraper conveyor according to an embodiment of the application.
Fig. 4 is a kinetic schematic diagram of a chain jump protection system for a scraper conveyor according to an embodiment of the application.
Reference numerals: 1. a sprocket vertical fine adjustment mechanism; 1.1, a connector; 1.2, stress sensor; 1.3, sprocket shafts; 1.4, an intermediate shaft; 1.5, universal adjusting piece; 1.6, steering shaft; 1.7, connecting disc; 1.8, connecting shaft; 1.9, a gear box; 2. a middle groove of the scraper conveyor; 3. a weighing sensor; 4. a horizontal tensioning hydraulic cylinder; 5. a vertical tensioning hydraulic cylinder; 6. a laser ranging sensor; 7. an upper computer; 8. an industrial personal computer; 9. signal conditioning box.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
In order to make the contents of the present application more clearly understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. It should be noted that the words "front", "back", "left", "right", "up" and "down" used in the following description refer to directions toward or away from the geometric center of a particular component, respectively, with reference to the directions in fig. 2.
Tension refers to a tensile force or traction force applied to an object or a system, and its direction is usually along the axis or stretching direction of the object; tension refers to the force applied to the surface of an object, typically to maintain the object in a tightly coupled or fixed state;
the chain is usually subjected to tension when in use, and when the chain is loaded or in motion, the interior of the chain is subjected to tension or traction, which is the tension to which the chain is subjected; the tensioning force is applied by a chain-connected tensioning device; in order to ensure the tight connection of the chains, a certain tension is required to be applied to adjust the tightness of the chains so as to achieve the optimal state; when the tension of the chain is too small, the chain is easy to jump or loose, so that proper balance between tension and tension is needed to ensure the normal work of the chain when the chain is used.
As shown in figures 1-2, the chain jump protection system of the scraper conveyor comprises a chain wheel vertical fine adjustment mechanism 1, a middle groove 2 of the scraper conveyor, a weighing sensor 3, a horizontal tensioning hydraulic cylinder 4, a vertical tensioning hydraulic cylinder 5, a laser ranging sensor 6, an upper computer 7, an industrial personal computer 8 and a signal adjustment box 9 which are arranged outside, wherein the right side of the chain wheel vertical fine adjustment mechanism 1 is fixedly connected with a motor of the scraper conveyor, the motor is fixedly arranged, a chain wheel of the scraper conveyor is rotationally arranged on a chain wheel base through a chain wheel shaft 1.3, the chain wheel base is movably arranged, the left side of the chain wheel vertical fine adjustment mechanism 1 is connected with the chain wheel shaft 1.3, a stress sensor 1.2 is arranged on the side surface of a chain wheel tooth, a laser ranging sensor 6 is arranged on one side of the chain wheel vertical fine adjustment mechanism 1, the weighing sensor 3 is arranged in the middle groove 2 of the scraper conveyor, the vertical fine adjustment mechanism 1 of the chain wheel is fixedly connected with the vertical extension end of the vertical tensioning hydraulic cylinder 5, the bottom of the vertical tensioning hydraulic cylinder 5 is connected with the ground through a sliding rail, the vertical tensioning hydraulic cylinder 5 can synchronously and transversely move with a chain wheel base, the horizontal tensioning hydraulic cylinder 4 is horizontally arranged on the ground, the extension end of the horizontal tensioning hydraulic cylinder 4 is fixedly connected with the chain wheel base, the stress sensor 1.2 is used for measuring stress data of chain wheel teeth under different tensions of a chain in the operation process of the scraper conveyor, the weighing sensor 3 is used for measuring coal dropping weight in each operation period of the scraper conveyor, the laser ranging sensor 6 is used for measuring the vertical distance from a meshing point of the chain wheel and the chain to a middle groove 2 of the scraper conveyor, the stress sensor 1.2, the weighing sensor 3 and the laser ranging sensor 6 are electrically connected with the signal adjustment box 9, the signal adjustment box 9 is electrically connected with the industrial personal computer 8, the industrial personal computer 8 is electrically connected with the upper computer 7, the signal conditioning box 9 can condition output signals of the stress sensor 1.2, the weighing sensor 3 and the laser ranging sensor 6 into voltage signals which can be identified by the industrial personal computer 8, the industrial personal computer 8 transmits data acquired by the stress sensor 1.2, the weighing sensor 3 and the laser ranging sensor 6 to the upper computer 7 through a TCP/IP protocol, and specifically, the laser ranging sensor 6 is a ZYT-405 type regional ranging detection control sensor, and the horizontal tensioning hydraulic cylinder 4 and the vertical tensioning hydraulic cylinder 5 are servo valve control type hydraulic cylinders.
In one embodiment, in combination with fig. 2, the sprocket vertical fine adjustment mechanism 1 comprises a connector, a stress sensor 1.2, a sprocket shaft 1.3 and a constant velocity universal transmission shaft structure, the extending end of the vertical tensioning hydraulic cylinder 5 is fixedly connected with the constant velocity universal transmission shaft structure through the connector, the constant velocity universal transmission shaft structure is fixedly connected with the sprocket shaft 1.3, the constant velocity universal transmission shaft structure is fixedly connected with an output shaft of a motor of the scraper conveyor, wherein the constant velocity universal transmission shaft structure comprises an intermediate shaft 1.4, a universal adjusting piece 1.5, a steering shaft 1.6, a connecting disc 1.7, a connecting shaft 1.8 and a gear box 1.9, the universal adjusting piece 1.5 is fixedly connected with the extending end of the vertical tensioning hydraulic cylinder 5 through the connector, the universal adjusting piece 1.5 is in spherical hinge connection with one end of the steering shaft 1.6 through the intermediate shaft 1.4, the other end of the steering shaft 1.6 is in meshed transmission connection with the gear box 1.9, the gear box 1.9 is fixedly connected with the connecting shaft 1.7 through the connecting shaft 1.8, the output shaft 1.7 is in particular connected with the motor through the connecting disc 1.7, and the sprocket shaft 1.5 can be driven to rotate through the connecting disc 1.3, and the sprocket shaft 1.3 can be driven to rotate through the connecting disc 1.3 and the sprocket shaft 1.3.
In the design, compared with the traditional single transverse adjustment mode of chain tension of the scraper conveyor, the application designs the vertical fine adjustment mechanism 1 of the chain wheel, realizes the vertical fine adjustment of the chain wheel to tension the chain by utilizing the constant-speed universal transmission shaft structure and the vertical tensioning hydraulic cylinder 5, and is easy to slightly shift when mechanical parts are matched due to the fact that the universal adjustment device of the constant-speed universal transmission shaft structure is connected with the steering shaft 1.6 through a precise spherical hinge, so that the engagement of the chain wheel and the chain is easier to realize.
In one embodiment, referring to fig. 3, a digital signal conversion module and a control signal conversion module are disposed in the industrial personal computer 8, an analog input conditioning module and an analog output conditioning module are disposed in the signal conditioning box 9, specifically, the digital signal conversion module selects an AD board PCI-1716, the control signal conversion module selects a DA board PCI-6208, an analog input conditioning module and an analog output conditioning module are disposed in the signal conditioning box 9, the analog input conditioning module converts 4-20 mA current signals output by the weighing sensor 3 and the laser ranging sensor 6 into-10V voltage signals that can be adopted by the AD board PCI-1716, then the AD board PCI-1716 transmits the signals to the industrial personal computer 8, then the industrial personal computer 8 transmits the signals to the upper computer 7, the upper computer 7 transmits a digital signal calculated by a controller model based on a catenary theory and a dynamics principle to the industrial computer 8, then the digital signal of the industrial computer 8 is converted into a voltage signal of-10V to 10V through a DA board PCI-6208, and is converted into a current signal of-40 mA to 40mA through an analog output conditioning module to drive a servo valve, the servo valve can control oil liquid of the vertical tensioning hydraulic cylinder 5 and the horizontal tensioning hydraulic cylinder 4, then the oil liquid output to the vertical tensioning hydraulic cylinder 5 and the horizontal tensioning hydraulic cylinder 4 is controlled to be used for realizing adjustment of chain tensioning force, the industrial computer 8 can transmit data acquired by the weighing sensor 3 and the laser ranging sensor 6 to the upper computer 7 through a TCP/IP protocol, and data acquired by the stress sensor 1.2 is transmitted to the upper computer 7 through a gigabit Ethernet through a DH5960 data acquisition device.
As shown in fig. 4, which is a dynamic schematic diagram of a scraper chain tensioning device of a scraper chain jump protection system of a scraper conveyor, a chain wheel drives a chain through meshing force, and a moment balance equation of the chain wheel is as follows:
in the formula (1), θ m And theta s Angular displacement of the driving device and the sprocket respectively; j (J) m Equivalent moment of inertia for the tail sprocket drive; b (B) m Is a damping coefficient; m is M m And M s The output torque of the motor and the load torque of the chain wheel are respectively; z is Z s Is the transmission ratio of the gear reducer; r is R 0 The pitch circle radius of the chain wheel is mu, the friction coefficient of the surface of the middle groove is mu, G is the weight of random coal falling and is measured by the weighing sensor 3, and L is the center distance of the chain wheels at the tail of the machine head.
The chain is provided with uniform quality, the chain on the no-load side is supported by the bottom plate of the middle groove, and the chain on the no-load side of the tail is in a suspension shape, so that the meshing angle of the E-point chain is deduced by using a catenary equation. According to fig. 3, in combination with the linear mass density λ of the chain and the boundary condition y' (L-a/2) =0, the catenary sag equation of the tail-side EF section can be established as:
wherein a is the length of the catenary in the horizontal direction; t (T) F The chain tension at the point F is measured by the stress sensor 1.2, and the catenary refers to the chain connecting the flights in the flight conveyor.
The formulas (1) and (2) are combined and decomposed along the horizontal and vertical directions to obtain the horizontal and vertical tensioning hydraulic cylinder tensioning forces which are respectively as follows:
F h (T F ，G，h E ，h B )＝(μGL/R 0 -T F /cosα)/cosβ+T F formula (3)
F v (T F ，G，h E ，h B )＝(μGL/R 0 -T F Formula/sin alpha/sin beta (4)
Wherein the engagement angles alpha and beta can be obtained by chain configuration analysis:
wherein S is 1 And S is 2 The chain lengths of the loaded side and the unloaded side are respectively h B And h E The chain hanging quantity at the loaded side and the unloaded side are respectively measured by a laser ranging sensor 6.
The application controls the working principle:
(1) Association relation between chain tension and chain wheel stress
The scraper conveyor drives the movement of the chain to realize the transportation of coal through the rotating chain wheel, and the tension of the chain and the deformation of the side surface of the chain wheel have direct association relation, such as: the tension abrupt change and unbalance of the chain tension generated by the chain jump can be expressed in real time through the stress value at the corresponding position of the chain wheel. By correlating the tension of the flight conveyor chain with the change in stress at key locations of the sprocket teeth, a measurement of chain tension can be achieved.
(2) Setting threshold value for fault detection
The working process of the scraper conveyor takes a working period with a certain length, the tension and the overhang quantity of the scraper chain in each period have certain rated values, the chain jump fault under the condition of extremely overload can occur when the tension and the overhang quantity exceed certain rated values, and the fault detection of the chain jump can be realized by setting the tension and the overhang quantity threshold.
(3) The industrial personal computer 8 controls the hydraulic cylinder to move
In each working period, the coal falling weight G can be regarded as a fixed value and is measured by the weighing sensor 3, and the chain tension T F Sag h E 、h B The stress sensor 1.2 and the laser ranging sensor 6 can be used for measuring respectively, all measured sensor output signals are conditioned to voltage signals which can be identified by the industrial personal computer 8, all data are transmitted to the upper computer 7 through a TCP/IP protocol, the upper computer 7 converts received data instructions into corresponding digital signals by combining the horizontal and vertical tensioning hydraulic cylinder tensioning force models, then the digital signals are converted into current signals by the signal conditioning box 9 to drive the servo valve, and oil liquid output to the horizontal and vertical tensioning hydraulic cylinders 5 is controlled to realize control of the movement of the hydraulic cylinders.
The protection method of the chain jump protection system of the scraper conveyor specifically comprises the following steps:
firstly, tension of a horizontal tensioning hydraulic cylinder 4 is obtained through tension adjustment of a scraper conveyor chain, so that the expansion and contraction of the horizontal tensioning hydraulic cylinder are controlled to control the expansion and contraction of the scraper conveyor chain; then, the tensioning force of the vertical tensioning hydraulic cylinder 5 is obtained through vertical fine adjustment of the chain wheel, so that the chain wheel is controlled to move upwards to tension the chain to prevent chain jump accidents, and whether the chain has chain jump faults or not is determined through fault discrimination of the scraper conveyor in the vertical fine adjustment of the chain wheel.
Specifically, the specific steps of chain tension adjustment of the scraper conveyor are as follows: firstly, establishing a correlation model of chain tension of the scraper conveyor and stress at the mounting position of the stress sensor 1.2 through a dynamic principle in one working period of the scraper conveyor (as shown in fig. 4 and the description above); then, the installed stress sensor 1.2 is calibrated through an external standard tension sensor, and the chain tension of the scraper conveyor is obtained through the output of the stress sensor 1.2; finally, the tensioning force of the horizontal tensioning hydraulic cylinder 4 is obtained from the obtained chain tension and the data measured by the load cell 3 by using a derived dynamic model (as shown in the above derived formula), thereby controlling the extension and retraction of the horizontal tensioning hydraulic cylinder 4 to control the extension and retraction of the scraper conveyor chain.
Specifically, the sprocket vertical fine adjustment comprises the following specific steps: firstly, on the basis of tension adjustment of a chain of a scraper conveyor, a laser ranging sensor 6 is utilized to measure the vertical distance from the lower engagement point of a chain wheel and the chain to the bottom plate of a middle groove 2 of the scraper conveyor; then, judging whether the chain has a chain jump fault or not through judging the fault of the scraper conveyor; finally, on the basis of determining the chain jump fault, the tensioning force of the vertical tensioning hydraulic cylinder 5 is obtained by combining data measured by the laser ranging sensor 6, the stress sensor 1.2 and the weighing sensor 3, and the chain wheel is controlled to move upwards to tension the chain so as to prevent the chain jump accident.
Specifically, the specific steps of fault discrimination of the scraper conveyor are as follows:
(a) Firstly, setting the vertical distance from the lower meshing point of a chain wheel and a chain to the bottom plate of a middle groove 2 of the scraper conveyor and the safety threshold value of the chain tension value as X and Y according to historical data under the normal operation condition of the scraper conveyor;
(b) Then, the vertical distance from the lower engagement point of the scraper conveyor sprocket and the chain to the bottom plate of the middle groove 2 of the scraper conveyor and whether the chain tension value T is larger than the set safety threshold values X and Y are respectively judged, and the specific judging method is as follows:
(b1) If not, the industrial personal computer 8 outputs a tension non-overrun signal;
(b2) If the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove 2 of the scraper conveyor is lower than a safety threshold X and the ratio of the tension value T of the chain to the tension threshold Y is suddenly changed, the industrial personal computer 8 outputs a scraper conveyor chain breakage judging signal;
(b3) If the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove 2 of the scraper conveyor does not exceed the safety threshold X, but the chain tension value T exceeds the set safety threshold Y, the industrial personal computer 8 outputs a scraper conveyor chain clamping judging signal;
(b4) If both the signals are yes, the industrial personal computer 8 outputs a scraper conveyor chain jump judging signal;
(c) Finally, once the upper computer 7 receives the chain jump judging signal of the scraper conveyor, the vertical tensioning hydraulic cylinder 5 is controlled to act, so that the chain wheel is driven to move upwards to tension the chain, and the chain jump accident is prevented.
The application converts the monitoring of chain tension of the scraper conveyor into the real-time detection of chain wheel stress, judges the fault condition of the chain of the scraper conveyor based on the on-line monitoring of the chain tension and the overhang quantity, and controls the running state of the chain by using the horizontal and vertical tensioning hydraulic cylinders 5.
The above embodiments are only for illustrating the technical solution of the embodiments of the present application, and are not limited thereto. Although embodiments of the present application have been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents substituted for elements thereof without departing from the spirit and scope of the application as defined in the claims.
Claims (10)
1. The utility model provides a scraper conveyor jump chain protection system, includes sprocket vertical fine setting mechanism (1), scraper conveyor middle part groove (2), weighing sensor (3), horizontal tensioning pneumatic cylinder (4), vertical tensioning pneumatic cylinder (5), upper computer (7), industrial computer (8) and signal conditioning case (9) of laser rangefinder sensor (6) and peripheral hardware, its characterized in that, the right side of sprocket vertical fine setting mechanism (1) and scraper conveyor's motor fixed connection, the motor is fixed setting, scraper conveyor's sprocket passes through sprocket axle (1.3) rotation and locates on the sprocket base, just the sprocket base is movable setting, the left side of sprocket vertical fine setting mechanism (1) with sprocket axle (1.3) are connected, sprocket tooth side-mounting is equipped with stress sensor (1.2), sprocket vertical fine setting mechanism (1) one side is equipped with laser rangefinder sensor (6), install in scraper conveyor middle part groove (2) and be equipped with weighing sensor (3), sprocket vertical fine setting mechanism (1) and vertical tensioning cylinder (5) are connected with horizontal tensioning cylinder (5) and horizontal tensioning cylinder (5) are connected with horizontal tensioning cylinder (5) hydraulic cylinder and horizontal tensioning cylinder are connected, the utility model provides a horizontal tensioning pneumatic cylinder (4) stretch out end and sprocket base fixed connection, stress sensor (1.2) are used for measuring the stress data of sprocket teeth under the different tension of scraper conveyor operation in-process chain, weighing sensor (3) are used for measuring the coal weight that falls in every operation cycle of scraper conveyor, laser rangefinder sensor (6) are used for measuring sprocket chain meshing point extremely the perpendicular distance of scraper conveyor middle part groove (2), stress sensor (1.2), weighing sensor (3) and laser rangefinder sensor (6) all with signal conditioning case (9) electric connection, signal conditioning case (9) and industrial computer (8) electric connection, industrial computer (8) and host computer (7) electric connection, just signal conditioning case (9) can with the output signal conditioning of stress sensor (1.2), weighing sensor (3) and laser rangefinder sensor (6) is industrial computer (8) identifiable voltage signal, industrial computer (8) are passed through to TCP (8) and are passed through to weighing sensor (6) IP sensor (6) and are gathered to upper computer (7).
2. The chain jump protection system of a scraper conveyor according to claim 1, characterized in that the sprocket vertical fine adjustment mechanism (1) comprises a connector (1.1), a stress sensor (1.2), a sprocket shaft (1.3) and a constant velocity universal drive shaft structure, the extending end of the vertical tensioning hydraulic cylinder (5) is fixedly connected with the constant velocity universal drive shaft structure through the connector (1.1), the constant velocity universal drive shaft structure is fixedly connected with the sprocket shaft (1.3), and the constant velocity universal drive shaft structure is fixedly connected with an output shaft of a motor of the scraper conveyor.
3. The chain jump protection system of a scraper conveyor according to claim 2, characterized in that the constant velocity universal drive shaft structure comprises a middle shaft (1.4), a universal adjusting piece (1.5), a steering shaft (1.6), a connecting disc (1.7), a connecting shaft (1.8) and a gear box (1.9), wherein the universal adjusting piece (1.5) is fixedly connected with the extending end of the vertical tensioning hydraulic cylinder (5) through the connector (1.1), the universal adjusting piece (1.5) is fixedly connected with the chain wheel shaft (1.3) through the middle shaft (1.4), the universal adjusting piece (1.5) is in spherical hinge connection with one end of the steering shaft (1.6), the other end of the steering shaft (1.6) is in meshed transmission connection with a gear box (1.9), the gear box (1.9) is fixedly connected with the connecting disc (1.7) through the connecting shaft (1.8), and the connecting disc (1.7) is fixedly connected with the output shaft of the motor.
4. The chain jump protection system of the scraper conveyor according to claim 1, wherein a digital signal conversion module and a control signal conversion module are arranged in the industrial personal computer (8), an analog input conditioning module and an analog output conditioning module are arranged in the signal conditioning box (9), the analog input conditioning module transmits output signals of the weighing sensor (3) and the laser ranging sensor (6) to the industrial personal computer (8) through the digital signal conversion module, and the industrial personal computer (8) transmits control signals to drive a servo valve through the control signal conversion module and the analog output conditioning module, so that oil liquid output to the vertical tensioning hydraulic cylinder (5) and the horizontal tensioning hydraulic cylinder (4) is controlled to be used for adjusting chain tensioning force.
5. The chain jump protection system of the scraper conveyor according to claim 4, wherein the laser ranging sensor (6) is a ZYT-405 type regional ranging detection control sensor, and the horizontal tensioning hydraulic cylinder (4) and the vertical tensioning hydraulic cylinder (5) are both servo valve control type hydraulic cylinders.
6. The method for protecting a chain jump protecting system of a scraper conveyor according to any one of claims 1 to 5, comprising the following steps:
in one working period of the scraper conveyor, establishing a correlation model of chain tension of the scraper conveyor and stress at the installation position of a stress sensor (1.2) through a dynamics principle; the installed stress sensor (1.2) is calibrated through an external standard tension sensor, and the chain tension of the scraper conveyor is obtained through the output of the stress sensor (1.2); the tension of the horizontal tensioning hydraulic cylinder (4) is obtained according to the obtained chain tension and the data measured by the weighing sensor (3) by utilizing the derived dynamic model, so that the stretching of the horizontal tensioning hydraulic cylinder (4) is controlled to control the stretching of the chain of the scraper conveyor to stretch the chain in the horizontal direction;
measuring the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove (2) of the scraper conveyor by using a laser ranging sensor (6); judging whether the chain has a chain jump fault or not through judging the fault of the scraper conveyor; on the basis of determining the chain jump fault, the tensioning force of the vertical tensioning hydraulic cylinder (5) is obtained by combining data measured by the laser ranging sensor (6), the stress sensor (1.2) and the weighing sensor (3), and the vertical tensioning hydraulic cylinder (5) is controlled to extend so as to control the chain wheel to move upwards to tension the chain, so that the chain jump accident is prevented.
7. The protection method of the chain jump protection system of the scraper conveyor according to claim 6, wherein the association model of the chain tension and the stress at the installation position of the stress sensor (1.2) is that the stress change of the corresponding positions of the chain tension of the scraper conveyor and the side surface of the sprocket tooth is measured in real time through the stress sensor (1.2) arranged on the side surface of the sprocket tooth, so that the measurement of the chain tension is realized.
8. The method of claim 6, wherein the derivation of the kinetic model comprises:
the moment balance equation of the chain wheel is as follows:
in the formula (1), θ m And theta s Angular displacement of the driving device and the sprocket respectively; j (J) m Is a tail sprocketEquivalent moment of inertia of the driving device; b (B) m Is a damping coefficient; m is M m And M s The output torque of the motor and the load torque of the chain wheel are respectively; z is Z s Is the transmission ratio of the gear reducer; r is R 0 The pitch circle radius of the chain wheel is mu, the friction coefficient of the surface of the middle groove is mu, G is the weight of randomly falling coal, and L is the center distance of the chain wheels at the tail of the machine head;
combining the linear mass density lambda of the chain and the boundary condition y' (L-a/2) =0, the suspension chain sag equation of the tail-side EF section is established as follows:
in the formula (2), a is the length of the catenary in the horizontal direction; t (T) F The chain tension at the point F is measured by the stress sensor (1.2);
the formulas (1) and (2) are combined and decomposed along the horizontal and vertical directions to obtain the horizontal and vertical tensioning hydraulic cylinder tensioning forces which are respectively as follows:
F h (T F ，G，h E ，h B )＝(μGL/R 0 -T F /cosα)/cosβ+T F formula (3)
F v (T F ，G，h E ，h B )＝(μGL/R 0 -T F Formula/sin alpha/sin beta (4)
Wherein the engagement angles alpha and beta can be obtained by chain configuration analysis:
in the formula (5), S 1 And S is 2 The chain lengths of the loaded side and the unloaded side are respectively h B And h E The chain sag is the load and no load side respectively.
9. The protection method of a chain jump protection system of a scraper conveyor according to claim 8, characterized in that the falling weight G is regarded as a constant value and passes through the load cell(3) Measured, the chain tension T F The sagging amount h is measured by the stress sensor (1.2) B And h E Are all measured by the laser ranging sensor (6).
10. The protection method of the scraper conveyor chain jump protection system according to claim 6, wherein the specific steps of the scraper conveyor fault discrimination are as follows:
(a) Firstly, setting the vertical distance between the lower meshing point of a chain wheel and a chain and the bottom plate of a middle groove (2) of the scraper conveyor and the safety threshold value of the chain tension value as X and Y according to historical data under the normal operation condition of the scraper conveyor;
(b) Then, respectively judging whether the vertical distance from the lower engagement point of the chain wheel and the chain of the scraper conveyor to the bottom plate of the middle groove (2) of the scraper conveyor and the chain tension value T are larger than set safety thresholds X and Y, wherein the specific judging method is as follows:
(b1) If not, the industrial personal computer (8) outputs a tension non-overrun signal;
(b2) If the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove (2) of the scraper conveyor is lower than a safety threshold value X and the ratio of the tension value T of the chain to the tension threshold value Y is suddenly changed, the industrial personal computer (8) outputs a scraper conveyor chain breakage judging signal;
(b3) If the vertical distance from the lower meshing point of the chain wheel and the chain to the bottom plate of the middle groove (2) of the scraper conveyor does not exceed the safety threshold X but the chain tension value T exceeds the set safety threshold Y, the industrial personal computer (8) outputs a scraper conveyor chain clamping judgment signal;
(b4) If both the signals are yes, the industrial personal computer (8) outputs a chain jump judging signal of the scraper conveyor;
(c) Finally, once the upper computer (7) receives the chain jump judging signal of the scraper conveyor, the vertical tensioning hydraulic cylinder (5) is controlled to act, so that the chain wheel is driven to move upwards to tension the chain, and the chain jump accident is prevented.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117228227A (en) * | 2023-09-11 | 2023-12-15 | 中国矿业大学 | Intelligent monitoring and chain-feeding device of heavy mining scraper conveyor and control method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117228227A (en) * | 2023-09-11 | 2023-12-15 | 中国矿业大学 | Intelligent monitoring and chain-feeding device of heavy mining scraper conveyor and control method |
| CN117228227B (en) * | 2023-09-11 | 2024-04-02 | 中国矿业大学 | Intelligent monitoring and chain-feeding device of heavy mining scraper conveyor and control method |
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